sedimentary

Red Sandstone

Ferruginous Sandstone (SiO2 with Fe2O3)

AI-generated identification · may be incorrect

Hardness: 6-7 (Mohs); Color: Red, reddish-brown, pink; Luster: Dull, earthy; Crystal structure: Clastic (sand-sized grains); Cleavage: None; Specific gravity: 2.2-2.8

Hardness: 6-7 (Mohs)
Color: Red, reddish-brown, pink
Luster: Dull, earthy

Identified July 15, 2026More sedimentary →

Explore Red Sandstone in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Hardness: 6-7 (Mohs); Color: Red, reddish-brown, pink; Luster: Dull, earthy; Crystal structure: Clastic (sand-sized grains); Cleavage: None; Specific gravity: 2.2-2.8

Formation & geological history

Formed through the accumulation and cementation of mineral particles or rock fragments, typically in desert or river delta environments. The red color is caused by the oxidation of iron minerals like hematite coating the quartz grains.

Uses & applications

Commonly used as a building material, paving stone, and in decorative landscaping. Historically significant in the construction of cathedrals and monuments.

Geological facts

Famous red sandstone formations include the Grand Canyon and the 'Old Red Sandstone' of Great Britain. It is a porous rock that often acts as an aquifer for groundwater.

Field identification & locations

Identified by its gritty, sandpaper-like feel and visible grains. Often found in layered beds or outcrops. Collectors look for unique bedding patterns or fossil inclusions.